1. Technical Field
This disclosure relates to analysis and correction of crosstalk between signals. In particular, this disclosure relates to a technique for more accurately determining the amount of crosstalk between signals, which may be useful in determining the levels of the underlying signals.
2. Description of the Related Art
It is a well-known problem in many different technical fields that measured signals may sometimes exhibit crosstalk. Crosstalk can, for example lead to erroneous changes in the data from one channel as a result of changes in a neighboring channel, which may impede the ability to determine the levels of the underlying signals in each channel. Accordingly, determining the amount of crosstalk and how to accurately correct for it is an important issue in many different areas. This disclosure includes techniques of general applicability that may be applied in different situations according to various embodiments.
For example, this disclosure includes techniques that may be applicable in such varied fields as single-tube polymerase chain reaction (PCR) or DNA melt analysis, PCR or melt data from neighboring wells of a multi-well plate or other multi-well arrangement, capillary electrophoresis data (e.g., DNA sequencing), gas chromatography, multispectral imaging, dual-color fluorescence correlation spectrometry, electrical crosstalk, etc.
In one embodiment, this disclosure may be applied to quantitative polymerase chain reaction (qPCR) devices used to amplify nucleic acid sequences. Some such devices may typically have multiple spectral channels to allow for multiplexed reactions. A problem sometimes encountered is that spectral overlap of the absorption and emission spectra of the fluorescent species (e.g., fluorophores) used to measure the real-time products of the reaction leads to crosstalk between the spectral channels. The signature of crosstalk in qPCR data is that a change in one channel's data can be seen in another channel's data. Crosstalk can reduce the effective limit of detection of an assay or lead to inconsistent or incorrect assay results.
According to one known technique, and as discussed in more detail below, crosstalk may be estimated statically based on determined characteristics of the measuring device. Such a method may have various drawbacks, however. The levels of crosstalk may in fact not be completely static, which can cause inaccuracies in the static estimate as the crosstalk varies. Accordingly, this disclosure provides various methods for determining crosstalk dynamically, based on analysis of the captured data.